JPS5912566A - Organic electrolyte battery - Google Patents

Abstract

PURPOSE:To make discharge voltage flat and prevent bulging of a battery by using a mixture of iron sulfide and cupric oxide as a positive active mass and making particle sizes of cupric oxide 1/2 or less of those of iron sulfide. CONSTITUTION:A positive electrode 1 constructed with a positive active mass comprising a mixture of iron sulfides and cupric oxides having particle sizes of 1/2 or less of those of iron sulfides, a negative electrode 7 using lithium as an active mass, and a separator 3 are accommodated into a positive can 4 and a negative can 5. They are sealed with a gasket 8 interposed to form an organic electrolyte battery. Since cupric oxide particles having smaller size exist in surroundings of iron sulfide particles, Cu generating by reaction acts as conductive material to increase discharge capacity and generated Li2S makes dense. Therefore, bulging of a battery by discharge is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION An object of the present invention is to improve an organic electrolyte battery, in particular to suppress swelling of the battery due to discharge, and to improve the amount of discharged electricity.

Organic electrolyte batteries that use iron sulfide or cupric oxide as positive electrode active materials have a larger electrical capacity per unit volume and have a higher discharge capacity than organic electrolyte batteries that use manganese dioxide or carbon fluoride as positive electrode active materials. The cell voltage is approximately 1.5V, making it compatible with commercially available Lecrancier batteries and silver oxide batteries, and its development as a high energy density battery with a large electrical capacity is expected.

However, when iron sulfide is used as a positive electrode active material, there are problems such as discharge products accumulating on the positive electrode, causing the positive electrode to swell and increase in volume, causing the battery to swell and damaging equipment using the battery. In addition, when cupric oxide is used as a positive electrode active material, there are disadvantages such as a two-stage discharge reaction and a lack of flatness of the discharge voltage. It did not end up being used as a weapon.

Therefore, the present inventors have conducted extensive research in order to obtain a battery that takes advantage of the advantages of iron sulfide and cupric oxide while eliminating their drawbacks. An organic electrolyte that, when mixed and used as a positive electrode active material, has a more even discharge voltage, less battery swelling due to discharge, and a larger discharge amount of electricity than either of them when used alone. He discovered that a battery could be obtained and had already filed a patent application for it, but as a result of further research, he discovered that by regulating the particle size of iron sulfide and cupric oxide, it was possible to produce a battery that could be released on the market. The present invention was completed based on the discovery that it is possible to further reduce the blowout of the battery caused by this, and to further improve the amount of discharged electricity.

That is, the present invention provides an organic electrolyte battery in which lithium is used as a negative electrode active material and a mixture of iron sulfide and second steel oxide is used as a positive electrode active material. The present invention relates to an organic electrolyte battery characterized in that the particle size of sulfide is 172 or less.

In the present invention, by making the particle size of the second oxidized steel smaller than the particle size of iron sulfide, it is possible to suppress the swelling of the battery due to discharge and improve the amount of discharged electricity. Although it is not always clear, if small-sized cupric oxide particles exist around iron sulfide particles, for example, the following 0T) Fe 52 + 4 L 1 →F
e + 2 L) 2 S (■
)CuO+ 2Li −+ Cu −to L
i20
([Cu +L+ 2 produced by D reaction
0 is generated in a concave manner around the − of F e S 2, and C
When u is mixed with the conductive additive, the utilization rate of the positive electrode active material is improved, and the amount of discharged electricity is improved.
Since i2S is surrounded by Cu and Li2O, it has a high bulk density, and it is thought that the swelling of the battery due to discharge is suppressed. In addition, since many small-sized cupric oxide particles exist around the iron sulfide, lithium oxysulfide, which has a higher bulk density than L l 20, is more likely to be generated as a discharge product. It is also possible.

As mentioned above, the particle size of cupric oxide is 1 of the particle size of iron sulfide.
//2 or less, but more preferably the particle size of cupric oxide is 174 or less of the particle size of iron sulfide. In addition, in the present invention, all particle sizes mean average particle sizes.

In the present invention, iron sulfides include, for example, ferrous sulfide (Fes), ferric sulfide (Fe2s3), iron disulfide (
When expressed by the general formula FexS, X
A material whose value is much smaller than 1 can also be used in the same way as FeS. (for example, propylene carbonate, r-butyrolactone, tetrahydrofuran, 1,2-dimethoxyethane, dioquinolane, etc.) or lithium perchlorate in a mixed solvent on 1d,
It is preferable to use a solution obtained by dissolving an electrolyte such as lithium fluoroborate.

Ratio of use of iron sulfur arsenide and cupric oxide -cI'i
It depends on what kind of properties you want to have more of, but the iron sulfide content of oketsu is 40 to 8 degrees (weight 1
The second oxidized steel is preferably in the range of 60 to 2°.

The present invention will be explained with reference to examples.

As shown in Table 1, iron disulfide (
Gold was produced using various grain sizes of FeS2) and cupric oxide (CtlO) as shown in Figure 1.

The resulting battery was made into a 20″C115 ohm with a final voltage of 1.2V.
1'. Emissions when discharged: 'Table 1 shows the swelling of the battery and the city air.

Table 1 The battery used in the test had the configuration shown in Figure 1, and the positive electrode (1) contained 41.5 parts of iron disulfide (parts by weight, hereinafter the same) with the particle size shown in Table 1 above. ), cupric oxide 4],
5 parts of acetylene black and 2 parts of polytetrafluoroethylene.
It is press-molded with a diameter of 11 mm and a thickness of 1.0 ffjlK. (2) is an annular pedestal made of #II stainless steel that is fixed to the periphery of the positive electrode (1) during pressure molding of the positive electrode, (3) is a separator made of polypropylene nonwoven fabric, and (4) is made of iron and has an outer surface. (5) is an electrode can made of a nickel-stainless steel clad plate, and a stainless steel mesh (6) is spot welded to the inner surface of this electrode can (5). A lithium plate having a diameter of 8 mm and a thickness of 0.9 mm is crimped onto this net (6) to constitute a negative electrode (7). (8) is an annular gasket made of polypropylene.

This battery has a diameter of 11.6 nm and a height of 3.0 vM, and the electrolyte contains a mixed solvent of propylene carbonate and 1,8-dioxolane with a volume ratio of 1:1, and 0.00 m of lithium perchlorate.
A solution dissolved at a rate of 5 mol/l is used;
5 μl is injected into the cell.

As shown in Table 1, when the particle size of cupric oxide is 1/2 or less of the particle size of iron disulfide, the amount of discharged electricity is large and the battery swelling is small. In particular, even more favorable results can be obtained when the particle size of cupric oxide is 174 times smaller than the particle size of iron disulfide.

[Brief explanation of the drawing]

FIG. 1 shows one embodiment of the organic electrolyte battery of the present invention (1).
...Masaka, (7)...Negative electrode patent applicant Hitachi Maxell Co., Ltd. representative t111 personal speech un-J-: Miwa Tetsui 1-
'1-L,

Claims (1)

[Claims] 1. In an organic electrolyte battery in which IJ thium is used as a negative electrode active material and a mixture of iron sulfide and cupric oxide is used as a positive electrode active material, the particle size of the cupric oxide is adjusted to An organic electrolyte battery characterized in that the particle size of the sulfide is 1/2 or less. 2. The organic electrolyte battery according to claim 1, wherein the particle size of the cupric oxide is 174 times smaller than the particle size of the iron sulfide.